This study was concerned at a limestone quarry located southeast of Helwan city, Egypt, in order to investigate the effect of hydric swelling on the geomechanical aspects of limestone rocks. The Volume of Egyptian limestones change due to the presence of clay minerals (swelling/shrinking). These changes in volume induced by changing environmental conditions, high temperature and fluctuation of the relative humidity, causes accelerated physical deterioration of limestone. The rainfall is infrequent, and it is usual for the area to have no precipitation for successive months. There is a remarkable variability in daily temperature between summer and winter. The hot and arid environment that controls the geological development can affect the engineering behavior of local sedimentary stones. Petrographic investigation by scanning electron microscopy (SEM) of Helwan limestone (biomicritic limestone) revealed the existence of smectite and glauconite within the stone. The clay fraction extracted from Helwan limestone is equal to 10 % by weight. The analysis of oriented clay mounts by X-ray diffraction (XRD) confirmed the dominance of smectite in the clay fraction.To study the effect of the clay content on the mechanical behavior of Helwan limestone, hydric swelling tests were performed at first by using a displacement sensor, afterwards, the effect of a sequence of wetting/ drying cycles on the stone strength was determined by the unconfined compressive strength (UCS) test. Results confirmed that the strength loss of the limestone is directly proportional to the degree of swelling of the clay, as expected. This highlights the importance of this parameter for selecting stones in new construction or for replacing purposes, and for establishing preventive measurements to minimize this damage in historic buildings. 

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Background Plant-associated microbes (endophytes) have a significant relationship to enhance plant growth and crop productivity by producing proficient bioactive metabolites. Since endophytes promoted plant growth either directly by releasing active metabolites such as phytohormones or indirectly by suppressing the growth of phytopathogens, so, in this work, biomass yield of local endophytic Trichoderma harzianum was maximized at shake-flask scale and scaled up via 7-L Bioflo310 fermenter using continuous exponential fed-batch fermentation mode. Subsequently, the effect of these cells as bio-fertilizer was assessed using two-barley grain genotypes (Russian and Egyptian seeds) via an intelligent hydroponic system based on Internet of Things (IoT). Results To reduce the cost of a biomass production line, agro-waste media containing potato, onion, garlic, pea, and cabbage peels were chosen as the culturing medium. The pea peel medium was found to be the best producer of biomass (2.2 g/L). The cultivation factors were evaluated to improve this biomass yield. The results showed that the maximum biomass production (4.9 g/L) was reported by adjusting the medium pH at 5.0 that inoculated with 10% of spore suspension, then incubated at 30°C, and 200 rpm. Then, this biomass yield was scaled up kinetically (505.4 g/L) by using exponential fed-batch fermentation mode via a 7-L bioreactor. The stimulation impacts of this endophytic T. harzianum on the growth of different barley genotypes (Russian and Egyptian seeds) were determined using a controlled hydroponic chamber. The total chlorophyll, carotenoid, and carbohydrate amounts in treated Russian showed the proficient stimulation percentage (81.05, 80, 40.8%) compared to the Egyptian barley groups (76.39, 73.5, 25.9%) respectively. Also, the maximum carbohydrate content (83.95 ± 1.7%) was recorded in the case of Russian barley. Conclusion Via this work, the optimal combination conditions for the cost-effective biomass production of endophytic T. harzianum were designed industrially via a fed-batch fermentation system using the cheapest culturing medium. Furthermore, by applying this promising bio-fertilizer, the total cost of barley production via an IoT hydroponic growing system was reduced. Besides, these animal diets (sprouted barley) could be produced in 3 cycles per month.